4×6 describes a label; A4 describes a sheet
A four-by-six-inch label measures 101.6 × 152.4 mm. A4 paper measures 210 × 297 mm. That does not mean the postage label itself becomes A4-sized: an A4 PDF may place the postage area on part of the sheet, with a receipt, instructions or despatch note elsewhere.
The practical comparison is between workflows. A thermal printer feeds individual adhesive labels and prints using heat-sensitive stock. An ordinary inkjet or laser printer feeds sheets, which might be plain paper or a compatible adhesive sheet. The downloaded file needs to suit whichever arrangement you choose.
Several similar names cause avoidable confusion. “6×4” normally reverses the same dimensions. “100 × 150 mm” is close to four by six inches but slightly smaller. A6 is a separate size, 105 × 148 mm. Check measurements on the pack and in the print dialogue instead of treating all three names as interchangeable.
Compare the physical outlines
See which dimensions actually fit
The full page, an adhesive label cell and the printer’s printable area are separate measurements. Start with the physical rectangle, then check the supported print layout.
A4 and 4×6 at the same scale
A4 sheet210 × 297 mm
Exact 4×6 label101.6 × 152.4 mm
The two close-ups use the same enlarged scale and align the top-left corners. L7169 is shown with its 99.1 mm side across and its 139 mm side down, rotating the manufacturer’s stated 139 × 99.1 mm dimensions.
Will an exact 4×6 page fit at 100%?
Compare the short and long edges after choosing portrait or landscape. These results concern physical boundaries; printer margins, template positioning and carrier requirements need their own checks.
| Destination | Short × long side | Fits at 100%? | What the dimensions tell you |
|---|---|---|---|
| Exact 4×6-inch stock | 101.6 × 152.4 mm | Yes, geometrically | Same nominal rectangle. Still check the printer’s printable area and supported media. |
| Full A4 sheet | 210 × 297 mm | Yes, geometrically | Fits within the full sheet. Adhesive cells, page margins and paperwork can use that space differently. |
| A6 paper | 105 × 148 mm | No | 3.4 mm spare across the short side; the long side is 4.4 mm too short. |
| Stock marked 100 × 150 mm | 100 × 150 mm | No | The nominal rectangle is 1.6 mm narrower and 2.4 mm shorter than exact 4×6. |
| One Avery L7169 cell | 99.1 × 139 mm | No | After matching orientation, the cell is 2.5 mm narrower and 13.4 mm shorter. |
Dimensions, sources and comparison method
One inch is exactly 25.4 mm, so 4 × 25.4 = 101.6 mm and 6 × 25.4 = 152.4 mm. NIST’s inch definition.
Brother’s paper-size table gives A4 as 210 × 297 mm and A6 as 105 × 148 mm. Avery lists each L7169 label as 139 × 99.1 mm. Brother paper sizes · Avery L7169 dimensions.
For each rectangle, put the shorter side first and compare both sides. A 100% edge-aligned fit requires the destination’s short side to be at least 101.6 mm and its long side at least 152.4 mm. Rotating by 90° changes orientation, while the two side lengths remain the same. The table considers those edge-aligned portrait and landscape orientations.
The clearances are destination minus source: A6 gives 105 − 101.6 = 3.4 mm across and 148 − 152.4 = −4.4 mm down. L7169 gives 99.1 − 101.6 = −2.5 mm across and 139 − 152.4 = −13.4 mm down. Negative clearance means the source extends outside that boundary. The 100 × 150 mm row compares the stated nominal dimensions; check the measurements of any specific pack.
Outlines show nominal physical sizes with squared corners and omit printer margins, label corner radii, adhesive-sheet gutters and manufacturing tolerances. They illustrate the comparison and provide no print template. Reviewed in November 2026.
Choose by your dispatch routine
| Your situation | Practical starting point | Check before committing |
|---|---|---|
| Occasional parcels and an existing A4 printer | Carrier’s A4 PDF on suitable paper | Attachment instructions and a complete, readable barcode |
| Frequent parcels from the same desk | Four-inch thermal printer and matching labels | Thermal PDF output, software support and supply system |
| Packing paperwork and labels together | Carrier’s A4 combined layout | Exact integrated sheet layout, if using adhesive stock |
| Small address or stock labels as well as parcels | Printer sized for the widest required job | A narrow address printer cannot accept full-width 4×6 stock |
Keep the first decision simple: download one representative postage file from the service you use. Check its page dimensions and available format settings. It is easier to choose suitable equipment after seeing the real document than to adapt a purchased printer to an assumed layout.
Thermal works well when labels are a repeated task
A suitable thermal setup removes the cutting and attaching step: print a label, peel it and apply it. Direct thermal printing needs compatible heat-sensitive labels rather than ink cartridges or toner. It can be convenient when you repeatedly move between weighing a parcel, buying postage and labelling the package.
Allow space for the whole supply arrangement. An external-feed printer needs a clear route from a fanfold stack or roll holder. A printer that contains its own rolls may give you a tidier footprint, while tying you to its particular media system. Include spare labels and cable access when measuring the desk.
The Brother QL-1100c below is a USB desktop option with a 101.6 mm print width and a built-in cutter. It uses supported Brother DK supplies. That makes it a different buying decision from an open-format machine that accepts generic fanfold stock; the printer price alone does not describe the ongoing setup.
Media width and printable width need separate checks. Brother specifies a maximum 101.6 mm printing width for the QL-1100/1100c and warns that full-width printing depends on the environment and margins. A label that physically contains the rectangle still needs a suitable printer setting and complete print preview. Brother QL-1100/1100c print-width and margin specifications
A fixed USB packing station
Brother QL-1100c shipping label printer
A wide-format choice for a seller who buys postage on a supported computer and prints at the same packing desk. The automatic cutter and Brother DK media make it convenient to alternate between supported die-cut and continuous labels.
Keep in mind. It is a USB model. Choose the network-equipped QL-1110NWBc if sharing the printer or using supported wireless printing is essential. Both depend on the Brother DK media system.
- 101.6 mm maximum print width
- USB computer connection
- Automatic cutter / Brother DK
Check the media system as well as the width. The MUNBYN fanfold labels below are relevant to a suitable open-format printer such as the RW403B. They are not an interchangeable refill for the QL-1100c. Brother’s wide shipping formats include DK-11247, which is larger than exact 4×6 stock; choose its supported driver setting and check the file fit.
Avoid buying a narrow label printer for a wide parcel workflow. A Brother QL-800 accepts media only up to 62 mm wide. It remains useful for addresses and smaller labels, but a wider roll cannot turn it into a full-width four-inch printer. Our thermal label supplies guide explains these compatibility checks.
Open-format fanfold supply
MUNBYN 4 × 6 inch fanfold shipping labels
A 500-label fanfold pack for compatible direct thermal shipping printers. The folded stack sits behind the printer and feeds without putting a large roll inside the machine.
Keep in mind. Check the actual printer’s width, gap sensing and feed instructions. These open-format labels are a different system from Brother DK holders and DYMO’s Series 5 authenticated rolls.
- 4 × 6 inch format
- 500 fanfold labels
- Direct thermal media
A4 can use the printer you already own
For occasional parcels, an existing A4 printer can be entirely practical. Royal Mail Click & Drop documents both six-by-four sticky labels and plain-paper printing with a household or office printer. Choose the correct output, then follow its instructions for attaching the label. Keep essential information flat and visible.
Adhesive A4 sheets avoid separately attaching plain paper, but introduce another alignment requirement. The postage area must fit the sheet’s cells and margins. An integrated label-and-despatch-note sheet has a particular label position; a four-per-sheet address layout has another. Both being A4 does not make them equivalent.
Avery L7169-100 is a laser product containing four 139 × 99.1 mm labels per sheet. It is useful when the intended address or parcel layout fits that format. It is not an exact 4×6 label, and it should not be presented as a universal adhesive sheet for every postage PDF.
Use the matching L7169 template and a suitable laser printer. Make an alignment check on plain paper before loading the adhesive stock. Follow the printer’s label-media and tray instructions, and use a fresh, complete sheet for one pass, as Avery recommends. An inkjet needs stock expressly suitable for its printing technology. Avery label-sheet feeding guidance
Four labels per A4 laser sheet
Avery L7169-100 A4 shipping label sheets
A four-per-sheet format for an existing laser printer. The Avery template gives each address a defined position on an A4 page, useful when dispatch volume does not justify a separate thermal machine.
Keep in mind. Each label is 139 × 99.1 mm, which differs from an exact 4 × 6 inch page. Use the correct L7169 template and laser-compatible printing instructions rather than stretching a carrier barcode to fill the label.
- 139 × 99.1 mm
- 4 labels per A4 sheet
- 100 laser sheets / 400 labels
Fix the output format before experimenting with scale
Start in the postage service, where the file is created. Royal Mail Click & Drop lists A4 integrated, A4 separate and six-by-four separate label/despatch-note templates. Other platforms have their own format settings. Select the appropriate output there before trying to compensate inside a PDF viewer.
A full A4 page reduced to a four-inch sheet will shrink everything, including the postage area. Cropping a file and scaling it are different operations: cropping changes the page boundary, whereas scaling changes the size of its contents. Prefer a correctly generated thermal PDF to repeatedly editing postage documents.
For a correctly sized label PDF, actual size or 100% avoids an accidental reduction when that agrees with the carrier’s instructions. It is still necessary to inspect the preview. Some printers have a smaller printable area than the nominal paper dimensions, so actual-size output can clip an edge. “Fit” may resolve clipping by reducing everything, but that does not establish that the resulting barcode meets the carrier’s requirements.
If the preview loses part of a label, recheck the selected stock, orientation and supported format. Use the carrier’s approved print settings or regenerate its correct template. Do not independently squeeze, stretch or remove parts of the barcode to make it fit a convenient sheet cell.
Keep despatch notes and customs documents in the workflow
Moving to a thermal printer changes the postage-label step. It does not automatically remove the need for other documents. A combined A4 layout can place a label and despatch note on one sheet; a separate thermal layout may leave the accompanying paperwork as a different print job.
Check a representative domestic order and any international workflow you use. Establish which documents stay with the parcel, which go inside it and which are required externally under the relevant service’s instructions. Keep the order reference visible in your packing process so a label does not end up beside the wrong invoice or parcel.
An A4 printer can therefore remain useful alongside a thermal machine. Decide where each document will print before switching the default printer, particularly if several people pack orders from the same computer.
Compare cost per usable label and the work around it
Use your own order pattern instead of a universal break-even number. For A4, count paper or adhesive sheets, ink or toner, and the time spent cutting or attaching. For thermal, include the printer, its particular label supply, any holder and the space occupied by stock.
Compare pack prices on the same basis: delivered cost divided by usable labels. A four-per-sheet pack can leave unused cells when jobs are small or the workflow cannot reuse a sheet. Thermal setup mistakes can waste labels too. A supply that is inexpensive per label is poor value if it repeatedly causes feed problems or does not match the machine.
Check one parcel before printing the rest
Confirm the PDF page size, physical stock and driver setting. Inspect the first print for complete text, intact barcodes and clear contrast. Apply it to a flat part of the parcel without folding essential information around an edge. Keep it clear of old labels or competing barcodes on reused packaging.
Save the successful settings, but recheck when changing a carrier, template or label pack. For the RW403B, our USB and Bluetooth setup guide takes you through the device connection separately from this format decision.
If you use Royal Mail, follow the Click & Drop A4 and 6×4 walkthrough to choose the template and regenerate the file. If your postage comes from a marketplace, use the download for that order.
Sources behind the format comparison
Product selection and print guidance were reviewed against manufacturer and carrier documentation in November 2026.
- Royal Mail: print Click & Drop labels and available label templates
- Brother QL-1100c specifications and DK-11247 supply
- Avery L7169-100 dimensions and laser compatibility and L7169 template
- NIST: exact inch-to-millimetre definition
- Brother: A4 and A6 paper dimensions and QL-1100/1100c printable-width limits
- Brother QL-800 media information and print-width specifications
- MUNBYN RW403B specifications
Common questions
Are 4×6 and 6×4 shipping labels different sizes?
They usually describe the same rectangular format with the dimensions stated in a different order. Exact four by six inches is 101.6 × 152.4 mm. Orientation and the actual stock dimensions still need to agree with the postage file and printer settings.
Is A6 exactly the same as a 4×6-inch label?
No. A6 is 105 × 148 mm, while exact 4×6 inches is 101.6 × 152.4 mm. Sellers sometimes use the terms loosely. Read the dimensions and use the size supported by your printer and the carrier’s output. A6 is 3.4 mm wider and 4.4 mm shorter, so an unchanged 4×6 page extends beyond its long edge.
Can I print shipping labels on ordinary A4 paper?
Royal Mail Click & Drop documents printing on plain paper using a household or office printer. Choose the appropriate A4 output and attach the label securely according to the carrier’s instructions. Other services may have different requirements.
Will Avery L7169 labels take an unchanged 4×6 PDF?
Do not assume so. L7169 has four 139 × 99.1 mm labels on an A4 sheet and is a laser printer product. Its cells are smaller than exact 4×6 inches. After aligning the short and long edges, the cell is 2.5 mm narrower and 13.4 mm shorter. Use a compatible layout and the matching template; do not shrink a carrier barcode arbitrarily to force it into the cell.
Should I always print a postage PDF at 100%?
Follow the carrier’s instructions for that exact file. With a correctly sized thermal PDF and matching stock, actual-size printing avoids unintended scaling, but printer margins can still clip content. Check the preview and the first print; change the correct template or approved settings instead of assuming one scale option fixes every file.